1. Field
The present disclosure relates generally to telecommunication systems, and more particularly, to concepts and techniques for video decoding in a receiver.
2. Background
In the world of telecommunications, where bandwidth comes at a premium, video encoding plays an important role. Video encoding can dramatically reduce the amount of information that must be sent across a transmission medium to reproduce a video image at the receiver. This is achieved by exploiting the fact there are very few differences between two adjacent frames in a video sequence. Often, the only difference is that some parts of the image have shifted slightly between frames. Video encoding is the process of generating information that represents this difference and then compressing that information.
At the receiver, the compressed information is decoded in order to recover the image. The amount of time required to decode each frame is dependent on the amount of information in that frame. When operating in real time, a video decoder should maintain an average decoding time of less than 1/(frame rate) “ TAVG”. However, despite sophisticated video encoding techniques, it is still possible that the real time constraints of the system will still not be met if a given number of frames have a high level of informational content. This may be especially true if the video decoding is performed by a central processing unit (CPU) that is shared with other receiver functions. If the real time constraints are not met, the video image may appear to stall or lose synchronization with the audio. In addition, video frames will be lost because there is not enough time to decode them all.
Accordingly, there is a need in the art for techniques to selectively drop frames in a video sequence to optimize the use of the receiver's computational resources, while at the same time minimize any reduction in picture quality when the video frames contain a high level of informational content.